Now to secretary of state john kerry. I spoke to him earlier this morning just after he sealed the deal. Thank you for joining us, secretary kerry. Will this stop iran's nuclear program in its track? Marco rubio said it will not freeze the irani nuclear program, it makes it more likely. Lindsey graham said -- your response? This negotiation is not the art of fantasy or the art of the ideal, it's the art of the possible which is verifiable and clear in its capacity to be able to make israel and the region safer. The fact is, that iran's ability to break out, george, will expand under this program. Therefore, israel will be safer, the region will be safer, iran's 20% uranium will be destroyed. Therefore they are safer. Iranian's stock will be frozen at its current level and the centrifuges will not be able to be installed in places that could otherwise be installed and advance the program. But not dismantle? The fact is, we'll have daily inspections. We will have daily inspections -- no, it's not. That's correct. That's the next step. Now, the choice people have is, do you want to sit there and argue that you have to dismantle your program before you stopped it, and while you're arguing about this dismantling it, they progress? In 2003, iran made an offer to the bush administration that they would, in fact, do major things with respect to their program, they had 164 centrifuges. Nobody took -- nothing has happened. Therefore, here we are in 2013, they have 19,000 centrifuges and they're closer to a weapon. You cannot sit there and pretend that you're just going to get the thing you want while they continue to move towards the program that they have been chasing. We've actually succeeded through the sanctions that congress put in place to be able to get to a point where we're locking in knowledgeably what their current leve and forcing them to go backwards, and while we go through these next six months, we will be negotiating the dismantling, we will be negotiating the limitations. But you can't always start where you want to wind up. Most people I talked to, who looked at this carefully, say the alternative that they're proposing just doesn't work. There also seems to be a clear difference between the united states d the iran on whether they have the right to enrich uranium. The foreign minister of iran says it includes it in two distinct places. I want to know, what is u.S. Position? Does the u.S. Respect and recognize that right of iran's? Yes or no? No, there is no right to enrich, we do not recognize a right to enrich. It is clear, in the npt -- in the nonproliferation treaty -- it is very clear that there is no right to enrich. Under the terms of this agreement, there will be a negotiation over whether or not they can have a very limited, completely verifiable, extraordinarily constrained program, where they might have some medical research or other things they can do, but there is no inherent right to enrich and everywhere in this particular agreement, it states that they could only do that by mutual agreement and that nothing is agreed on until everything is agreed on, that language appears at least twice in significant places in this agreement. So, there is no agreement that they can enrich, they have the ability to negotiate it, but they could only gain that capacity to have some enrichment as some countries do, if they live up to the whole set of terms necessary to prove its a peaceful program. So, iran has some very stiff hurdles they have to meet in order to do that. There is no right and no right granted in this agreement. We're seeing the first israeli -- they have a right according to npt. Let me just say, george, they do have the right, any country has the right in the npt to a peaceful nuclear program. There is a defined right within the npt. But a peaceful nuclear program does not mean you have the right to enrich. We just heard the israeli prime minister bibi netanyahu call it a bad deal. Are you confident that you can get him to respect it? Well, actually, israel and the united states absolutely share the same goal here. There is no daylight between us with respect to what we want to achieve at this point. We both want to make it certain that iran cannot have a nuclear weapon and iran cannot be in a place where they can break out and suddenly get that weapon. The deal is the beginning and first step, it leads us into the negotiation so that we guarantee that, while we are negotiating for the dismantling, while we are negotiating for the tougher provisions, they will not grow the program in their capacity to threaten israel. Israel will actually gain a larger breathing space in terms of the breakout capacity of iran. It's just clear. The u.S. Has pledged in this deal to hold off on new sanctions for six more months. The president says now is not the time for new sanctions. Are you confident that you can convince congress not to pass new sanctions? If they do, will the president veto them? Well, george, I believe congress will recognize that this deal actually has a great deal of benefit in it. And I look forward to going up and working with our colleagues on the hill in order to try to persuade them that this is not the moment to increase sanctions. I'm confident that, as congress examines what we have been able to achieve here, and as they measure the fact that if you didn't do what we were doing, they would be marching forward and putting more centrifuges in, enriching more, moving closer to a weapon. What we have done, absolutely, unequivocally, allows us to get in there and stop the enrichment. And if they're not prepared to do the things necessary, to be able to have a peaceful program, truly peaceful and provable as such, then the sanctions can be turned back up and of course, he always have every option available to him as commander in chief. Finally, mr. Secretary, you just emerged from the first face to face negotiations with irani iranians since 1979, is the u.S. Now heading toward a normal relationship with iran? How do you reconcile your words with their leader who accuses u.S. Of war crimes? Well, those are the most insulting and unacceptable terms, obviously that goes without stating. We don't accept that kind of terminology and we hope that's not going to be part of the future, we're not going to sit around and deal with hopes or words and pretend that there's trust where it has to be built over a long period of time, so we have no illusions, this is not going to change in one fell swoop and overnight. We have a long building process to engage in here. We need to put to test iran's words and intentions. Without any cobwebs, without any, you know, false assumptions, without any illusions, this is a hard road. And we will stand by israel 100% and I believe we will show that this particular approach has the ability to be able to garner greater, broader international support for whether or not iran is, in fact, following through on its commitments or not. If you ultimately have to hold them accountable because they're not doing it, you have to be able to show that you've gone through all of the diplomatic avenues available before considering other alternatives. Mr. Secretary, thank you very much for taking the time to be with us. Thanks, george. Thank you very much.

This transcript has been automatically generated and may not be 100% accurate.

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